# Vibration-rotation-tunneling dynamics in small water clusters

## Abstract

The goal of this work is to characterize the intermolecular vibrations of small water clusters. Using tunable far infrared laser absorption spectroscopy, large amplitude vibration-rotation-tunneling (VRT) dynamics in vibrationally excited states of the water dimer and the water trimer are investigated. This study begins with the measurement of 12 VRT subbands, consisting of approximately 230 transitions, which are assigned to an 82.6 cm[sup [minus]1] intermolecular vibration of the water dimer-d[sub 4]. Each of the VRT subbands originate from K[sub a][double prime]=0 and terminate in either K[sub a][prime]=0 or 1. These data provide a complete characterization of the tunneling dynamics in the vibrationally excited state as well as definitive symmetry labels for all VRT energy levels. Furthermore, an accurate value for the A[prime] rotational constant is found to agree well with its corresponding ground state value. All other excited state rotational constants are fitted, and discussed in terms of the corresponding ground state constants. In this vibration, the quantum tunneling motions are determined to exhibit large dependencies with both the K[sub a][prime] quantum number and the vibrational coordinate, as is evidenced by the measured tunneling splittings. The generalized internal-axis-method treatment which has been developed to model the tunneling dynamics, is consideredmore »

- Authors:

- Publication Date:

- Research Org.:
- Lawrence Berkeley Lab., CA (United States)

- Sponsoring Org.:
- USDOE; USDOE, Washington, DC (United States)

- OSTI Identifier:
- 6642535

- Report Number(s):
- LBL-33327

ON: DE93010427

- DOE Contract Number:
- AC03-76SF00098

- Resource Type:
- Technical Report

- Resource Relation:
- Other Information: Thesis (Ph.D.)

- Country of Publication:
- United States

- Language:
- English

- Subject:
- 74 ATOMIC AND MOLECULAR PHYSICS; WATER; ROTATIONAL STATES; VIBRATIONAL STATES; DIMERS; LASER SPECTROSCOPY; SOLID CLUSTERS; ENERGY LEVELS; EXCITED STATES; HYDROGEN COMPOUNDS; OXYGEN COMPOUNDS; SPECTROSCOPY; 664400* - Experimentally Derived Information on Atomic & Molecular Properties- (1992-)

### Citation Formats

```
Pugliano, N.
```*Vibration-rotation-tunneling dynamics in small water clusters*. United States: N. p., 1992.
Web. doi:10.2172/6642535.

```
Pugliano, N.
```*Vibration-rotation-tunneling dynamics in small water clusters*. United States. doi:10.2172/6642535.

```
Pugliano, N. Sun .
"Vibration-rotation-tunneling dynamics in small water clusters". United States. doi:10.2172/6642535. https://www.osti.gov/servlets/purl/6642535.
```

```
@article{osti_6642535,
```

title = {Vibration-rotation-tunneling dynamics in small water clusters},

author = {Pugliano, N},

abstractNote = {The goal of this work is to characterize the intermolecular vibrations of small water clusters. Using tunable far infrared laser absorption spectroscopy, large amplitude vibration-rotation-tunneling (VRT) dynamics in vibrationally excited states of the water dimer and the water trimer are investigated. This study begins with the measurement of 12 VRT subbands, consisting of approximately 230 transitions, which are assigned to an 82.6 cm[sup [minus]1] intermolecular vibration of the water dimer-d[sub 4]. Each of the VRT subbands originate from K[sub a][double prime]=0 and terminate in either K[sub a][prime]=0 or 1. These data provide a complete characterization of the tunneling dynamics in the vibrationally excited state as well as definitive symmetry labels for all VRT energy levels. Furthermore, an accurate value for the A[prime] rotational constant is found to agree well with its corresponding ground state value. All other excited state rotational constants are fitted, and discussed in terms of the corresponding ground state constants. In this vibration, the quantum tunneling motions are determined to exhibit large dependencies with both the K[sub a][prime] quantum number and the vibrational coordinate, as is evidenced by the measured tunneling splittings. The generalized internal-axis-method treatment which has been developed to model the tunneling dynamics, is considered for the qualitative description of each tunneling pathway, however, the variation of tunneling splittings with vibrational excitation indicate that the high barrier approximation does not appear to be applicable for this vibrational coordinate. The data are consistent with a motion possessing a[prime] symmetry, and the vibration is assigned as the [nu][sub 12] acceptor bending coordinate. This assignment is in agreement with the vibrational symmetry, the resultsof high level ab initio calculations, and preliminary data assigned to the analogous vibration in the D[sub 2]O-DOH isotopomer.},

doi = {10.2172/6642535},

journal = {},

number = ,

volume = ,

place = {United States},

year = {1992},

month = {11}

}